The objective of this proposal is to develop methods for the synthesis of novel bridged polycyclic compounds and biologically active alkaloids via intramolecular Diels-Alder reactions of dihydropyridines. Specific aims are (1) development of methods for the synthesis of the approrpriate 2-substituted-1, 2-dihydropyridines, which will be used as intermediates for the proposed intramolecular Diels-Alder cycloaddition reactions, (2) study of the intramolecular (pi2 + pi4) cycloaddition reaction of the above 1,2-dihydropyridines with regard to yield and regiospecificity, (3) development of a route to optically active 1,2-dihydropyridine intermediates via an asymmetric synthesis, and (4) investigation of approaches to the synthesis of biologically active alkaloids utilizing the above synthetic methods. The potential of these methods with regard to a shor and practical route to medicinally improtant alkaloids is discussed.